Transmission for hybrid electric vehicle

Abstract

A transmission for a hybrid electric vehicle may include an input element where rotation power may be inputted and an output element from which the rotation power may be outputted, a first motor generator and a second motor generator, a first planetary gear set where the input element, the output element, and the first motor generator may be connected, a second planetary gear set that may be a multiple planetary gear set where the output element and the second motor generator may be connected and that includes at least four or more rotary elements, and a first clutch and a second clutch.

What is claimed is: 
     
       1. A transmission for a hybrid electric vehicle, comprising:
 an input element where rotation power is inputted and an output element from which the rotation power is outputted; 
 a first motor generator and a second motor generator; 
 a first planetary gear set where the input element, the output element, and the first motor generator are connected; 
 a second planetary gear set that is a multiple planetary gear set where the output element and the second motor generator are connected and that includes at least four or more rotary elements; 
 a first clutch and a second clutch; 
 a third clutch that switches one rotary element to be rotatable, which is not connected with the output element, the first clutch, and the second clutch, in rotary elements of the second planetary gear set, in order to make a fixed gear stage when the second clutch operates, 
 wherein a first rotary element of the first planetary gear set and a first rotary element of the second planetary gear set are kept connected with the output element, 
 a second rotary element and a third rotary element of the first planetary gear set are connected with the input element and the first motor generator, respectively, 
 a second rotary element of the second planetary gear set is connected with the second motor generator, 
 a third rotary element of the second planetary gear set is switched to be rotatable by the first clutch, and 
 the third rotary element of the first planetary gear set and a fourth rotary element of the second planetary gear set are switched to be selectively connected by the second clutch. 
 
     
     
       2. The transmission for the hybrid electric vehicle according to  claim 1 , further comprising a fourth clutch that selectively connects the second rotary element of the first planetary gear set with the second rotary element of the second planetary gear set. 
     
     
       3. The transmission for the hybrid electric vehicle according to  claim 1 , wherein the first rotary element of the first planetary gear set is a carrier. 
     
     
       4. The transmission for the hybrid electric vehicle according to  claim 1 , wherein the first rotary element is a carrier, the second rotary element is a ring gear, and the third rotary element is a sun gear, in the first planetary gear set. 
     
     
       5. The transmission for the hybrid electric vehicle according to  claim 1 , wherein the first rotary element of the first planetary gear set is a ring gear. 
     
     
       6. The transmission for the hybrid electric vehicle according to  claim 1 , wherein the first rotary element is a ring gear, the second rotary element is a carrier, and the third rotary element is a sun gear, in the first planetary gear set. 
     
     
       7. The transmission for the hybrid electric vehicle according to  claim 1 , wherein the second planetary gear set is a multiple planetary gear set having a planetary gear set including the first, the second, and the third rotary elements and a planetary gear set including the first, the third, and the fourth rotary elements. 
     
     
       8. The transmission for the hybrid electric vehicle according to  claim 7 , wherein the first, second, and third rotary elements of the planetary gear set including the first, second, and third rotary elements of the second planetary gear set are a carrier, a sun gear, and a ring gear, respectively. 
     
     
       9. The transmission for the hybrid electric vehicle according to  claim 7 , wherein the first, third, and fourth rotary elements of the planetary gear set including the first, third, and fourth rotary elements of the second planetary gear set are a sun gear, a carrier, and a ring gear, respectively. 
     
     
       10. The transmission for the hybrid electric vehicle according to  claim 7 , wherein the first, third, and fourth rotary elements of the planetary gear set including the first, third, and fourth rotary elements of the second planetary gear set are a sun gear, a ring gear, and a carrier, respectively. 
     
     
       11. The transmission for the hybrid electric vehicle according to  claim 1 , further comprising the third clutch that switches the second rotary element connected with the second motor generator of the second planetary gear set to be rotatable in order to make a fixed gear ratio stage when the second clutch operates. 
     
     
       12. A transmission for a hybrid electric vehicle, comprising:
 a first planetary gear set including three rotary elements connected with an input element, an output element, and a first motor generator, respectively; 
 a second planetary gear set including at least four or more rotary elements having a rotary element connected to the output element, a rotary element having a same rotation speed as the rotation speed of the rotary element connected to the first motor generator of the first planetary gear set, and a rotary element connected to a second motor generator; 
 a second clutch connecting/disconnecting the rotary element of the second planetary gear set which has the same rotation speed as the rotation speed of the rotary element connected to the first motor generator of the first planetary gear set with/from the rotary element connected to the first motor generator of the first planetary gear set; 
 a first clutch that switches the rotatable state of one rotary element that is not connected to the output element, the second motor generator, and the second clutch, in the rotary elements of the second planetary gear set; and 
 a third clutch that switches the rotary element of the second planetary gear set which is connected with the second motor generator to be rotatable. 
 
     
     
       13. The transmission for the hybrid electric vehicle according to  claim 12 , further comprising a fourth clutch that connects/disconnects the rotary element, which is connected with the input element, of the first planetary gear set with/from the rotary element, which is connected with the second motor generator, of the second planetary gear set. 
     
     
       14. The transmission for the hybrid electric vehicle according to  claim 12 , wherein the first planetary gear set is a single pinion gear set,
 the rotary element connected to the input element of the first planetary gear set is a ring gear, 
 the rotary element connected to the output element of the first planetary gear set is a carrier, and 
 the rotary element connected to the first motor generator of the first planetary gear set is a sun gear. 
 
     
     
       15. The transmission for the hybrid electric vehicle according to  claim 14 , wherein the second planetary gear set includes two single pinion planetary gear sets including two pairs of rotary elements that are kept connected,
 a pair of the two pairs of rotary elements that are kept connected is connected to the output element, 
 and other pair of the two pairs of rotary elements that are kept connected is connected to the first clutch, and 
 other rotary element that are not included in the pairs are connected to the second motor generator and the second clutch, respectively. 
 
     
     
       16. The transmission for the hybrid electric vehicle according to  claim 15 , wherein in the two pairs of rotary elements of the second planetary gear set that are kept connected, a ring gear of one planetary gear set is connected to a carrier of another planetary gear set and a carrier of one planetary gear set is connected to a sun gear of the other planetary gear set.